Background: Since seaweed is a common component of the Japanese diet, iodine intake in Japanese is expected to be high. However, urinary iodine excretion, measured using 24-hour urine samples, and its dietary determinants are not known.Methods: Apparently healthy adults aged 20 to 69 years living in 20 areas throughout Japan were recruited in February and March, 2013. Urinary iodine excretion was evaluated using 24-hour urine collected from 713 subjects (362 men and 351 women), and the difference among age groups was assessed. The association between dietary intake of food groups and urinary iodine excretion was assessed among 358 subjects who completed a semi-weighed 4-day diet record (DR) and urine collection. The correlations between iodine intake and iodine excretion were also evaluated, and correlation coefficients were calculated for iodine intake in the DR of the overlapping day or the DR 1 day before and after urine collection.Results: Median iodine excretion in 24-hour urine was 365 µg, and excretion was significantly higher in older subjects. Iodine intake estimated by the DRs was significantly correlated with urinary iodine excretion when DRs and urine collection were obtained on the same day (r = 0.37). After adjustment for confounding factors, iodine excretion was significantly associated with intakes of kelp and soup stock from kelp and fish.Conclusions: Although multiple measurements for urinary iodine are required to confirm our results, this study showed the current iodine status of healthy Japanese adults. The results suggest that kelp and fish are the main contributors to Japanese iodine status measured by 24-hour urine.

Background: We examined the associations of informal (eg, family members and friends) and formal (eg, physician and visiting nurses) social support with caregiver’s burden in long-term care and the relationship between the number of available sources of social support and caregiver burden.Methods: We conducted a mail-in survey in 2003 and used data of 2998 main caregivers of frail older adults in Aichi, Japan. We used a validated scale to assess caregiver burden.Results: Multiple linear regression demonstrated that, after controlling for caregivers’ sociodemographic and other characteristics, informal social support was significantly associated with lower caregiver burden (β = −1.59, P < 0.0001), while formal support was not (β = −0.30, P = 0.39). Evaluating the associations by specific sources of social support, informal social supports from the caregiver’s family living together (β = −0.71, P < 0.0001) and from relatives (β = −0.61, P = 0.001) were associated with lower caregiver burden, whereas formal social support was associated with lower caregiver burden only if it was from family physicians (β = −0.56, P = 0.001). Compared to caregivers without informal support, those who had one support (β = −1.62, P < 0.0001) and two or more supports (β = −1.55, P < 0.0001) had significantly lower burden. This association was not observed for formal support.Conclusions: Social support from intimate social relationships may positively affect caregivers’ psychological wellbeing independent of the receipt of formal social support, resulting in less burden.

Background: There is little information regarding whether the combination of Helicobacter pylori (H. pylori) antibody and serum pepsinogen (sPG), which is a marker of the degree of atrophic gastritis, has a discriminatory ability for detecting incident gastric cancer. We examined this issue in a long-term prospective cohort study of a Japanese population.Methods: A total of 2446 Japanese community-dwelling individuals aged ≥40 years were stratified into four groups according to baseline H. pylori serological status and sPG: Group A (H. pylori[−], sPG[−]), Group B (H. pylori[+], sPG[−]), Group C (H. pylori[+], sPG[+]), and Group D (H. pylori[−], sPG[+]), and participants were followed up prospectively for 20 years.Results: During the follow-up, 123 subjects developed gastric cancer. Compared with that in Group A, the cumulative incidence of gastric cancer was significantly increased in Groups B, C, and D, whereas no significant difference was found between Groups C and D. The multivariable-adjusted risk of gastric cancer was significantly increased in Group B (hazard ratio [HR], 4.08; 95% confidence interval [CI], 1.62–10.28) and in Groups C and D combined (HR 11.1; 95% CI, 4.45–27.46). When the multivariable model with H. pylori antibody was changed into that with the combination of H. pylori antibody and sPG, the C statistics for developing gastric cancer increased significantly (0.773 vs 0.732, P = 0.005), and the continuous net reclassification improvement value was 0.591 (P < 0.001).Conclusions: Our findings suggest that the combination of H. pylori antibody and sPG is a useful tool for predicting the development of gastric cancer.

Background: Serum lipid trends in children and adolescents are predictors of the future prevalence of cardiovascular disease in adults.Methods: Data were obtained from cross-sectional studies conducted in 2004 and 2014. A total of 3249 children aged 6–18 years were included in the present study; serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) were measured.Results: Overall, upward trends in mean TC, non-HDL-C, and LDL-C levels, and in geometric mean TG levels, were observed (all P < 0.001). Mean HDL-C levels significantly decreased between 2004 and 2014 (from 1.54 mmol/L to 1.47 mmol/L; P < 0.001). The prevalence of abnormal levels of serum lipids, with the exception of the prevalence of low HDL-C (P = 0.503), significantly increased over the study period (all P < 0.05). The prevalence of hyperlipidemia (from 13.3%; 95% confidence interval [CI], 11.6%–15.0% to 24.5%; 95% CI, 22.4%–26.6%; P < 0.001) and dyslipidemia (from 18.8%; 95% CI, 16.9%–20.7% to 28.9%; 95% CI, 26.7%–31.3%; P < 0.001) also increased from 2004 to 2014. The prevalence of abnormal serum lipids increased, and mean serum lipid levels, with the exception of TC levels, worsened in subjects with obesity compared with non-overweight subjects, as well as in subjects with mixed obesity compared with non-obese subjects (P < 0.05 for all).Conclusions: Adverse trends in serum lipid concentrations over the past 10 years were observed among children aged 6–9 years, with the exception of specific lipids, and among adolescents aged 10–18 years, from several schools in Beijing, China.

Background: High attendance rates and regular participation in disease screening programs are important contributors to program effectiveness. The objective of this study was to examine the effects of an initial false-positive result in chest X-ray screening for lung cancer on subsequent screening participation.Methods: This historical cohort study analyzed individuals who first participated in a lung cancer screening program conducted by Yokohama City between April 2007 and March 2011, and these participants were retrospectively tracked until March 2013. Subsequent screening participation was compared between participants with false-positive results and those with negative results in evaluation periods between 365 (for the primary outcome) and 730 days. The association of screening results with subsequent participation was evaluated using a generalized linear regression model, with adjustment for characteristics of patients and screening.Results: The proportions of subsequent screening participation within 365 days were 12.9% in 3132 participants with false-positive results and 6.7% in 15 737 participants with negative results. Although the differences in attendance rates were reduced with longer cutoffs, participants with false-positive results were consistently more likely to attend subsequent screening than patients with negative results (P < 0.01). The predictors of subsequent screening participation were false-positive results (risk ratio [RR] 1.72; 95% confidence interval [CI], 1.54–1.92), older age (RR 1.17; 95% CI, 1.11–1.23), male sex (RR 1.46; 95% CI, 1.29–1.64), being a current smoker (RR 0.80; 95% CI, 0.69–0.93), current employment (RR 0.79; 95% CI, 0.70–0.90), and being screened at a hospital cancer center (vs public health centers; RR 1.36; 95% CI, 1.15–1.60).Conclusions: Our findings indicated that subsequent participation in lung cancer screening was more likely among participants with false-positive results in an initial screening than patients with negative results.

Background: Studies on the association between body mass index (BMI) and death risk among patients with hypertension are limited, and the results are inconsistent. We investigated the association between BMI and cardiovascular disease (CVD) and all-cause mortality among hypertensive patients in a population of Beijing, China.Methods: We conducted a prospective cohort study of 2535 patients with hypertension aged 40 to 91 years from Beijing, China. Participants with a history of CVD at baseline were excluded from analysis. Cox proportional hazards regression models were used to estimate the association of different levels of BMI stratification with CVD and all-cause mortality.Results: During a mean follow-up of 8.1 years, 486 deaths were identified, including 233 cases of CVD death. The multivariable-adjusted hazards ratios for all-cause mortality associated with BMI levels (<20, 20–22, 22–24, 24–26 [reference group], 26–28, 28–30, and ≥30 kg/m2) were 2.03 (95% confidence interval [CI], 1.48–2.78), 1.61 (95% CI, 1.18–2.20), 1.30 (95% CI, 0.95–1.78), 1.00 (reference), 1.12 (95% CI, 0.77–1.64), 1.33 (95% CI, 0.90–1.95), and 1.66 (95% CI, 1.10–2.49), respectively. When stratified by age, sex, or smoking status, the U-shaped association was still present in each subgroup (P > 0.05 for all interactions). Regarding the association of BMI with CVD mortality, a U-shaped trend was also observed.Conclusions: The present study showed a U-shaped association of BMI with CVD and all-cause mortality among patients with hypertension. A lowest risk of all-cause mortality was found among hypertensive patients with BMI between 24 and 26 kg/m2.